November 12, 2009—A new dinosaur unearthed in South Africa has given scientists a glimpse into the evolution of sauropods, the biggest animals ever to have walked the Earth, a new study says.© 2009 National Geographic (AP)
These fossils could prove to be a missing evolutionary link in our knowledge of dinosaurs.
Aardonyx celestae was a small-headed herbivore with a huge barrel chest that roamed the Earth about 200 million years ago.
The fossilized bones were unveiled in South Africa this week, to coincide with the publication of the scientists' findings in the Proceedings of The Royal Society B.
SOUNDBITE: (English), Adam Yates, Paleontologist, University of the Witswatersrand: "The first day of digging we started exposing large bone, after large bone. Bones far too large to belong to any Massospondylus and with many other anatomical features that suggested that this was not just another pile of Massospondylus bones we had something new and very very exciting."
The findings show that Aardonyx celestae walked on its hind legs but could drop to all fours. The specimen discovered stood nearly 6 feet high at the hip, but was believed to still be growing when it died. Its thought adults could have grown as high as 50 feet.
Aardonyx celestae has many characteristics of the plant-eating herbivores that walked on two legs as well as their descendants.
SOUNDBITE: (English), Adam Yates, Paleontologist, University of the Witwatersrand: "This is a new jewel in the crown of South Africa's heritage, and it's particularly significant because it's a very intermediate type of dinosaur. It sits very squarely between two different basic types of dinosaur. An earlier bipedal type of dinosaur usually called Prosauropods and a more advanced gigantic four-legged type of dinosaur called Sauropods."
The research was funded in part by a grant from National Geographic.
The team believes they may have stumbled onto a "paleontological oasis" in central South Africa that may yield further previously unknown dinosaur species.